Gene controls speed of disease progression in tuberculosis

According to researchers at the McGill University Health Centre, about one-third of people worldwide are infected by the bacteria which causes tuberculosis; mycobacterium tuberculosis.

“Of the estimated two billion people infected, only 5%-10% actually develop tuberculosis disease in their lifetime–the other 90%-95% appear to be able to contain the infection in a dormant state, so that they do not become ill,” explained Dr Erwin Schurr, a molecular geneticist at the Centre for the Study of Host Resistance at the MUHC, and the study’s principal investigator.

The new research focused on NRAMP1, a gene already known to be involved in many other illnesses such as leprosy and rheumatoid arthritis. The researchers discovered that alleles, or variants of the NRAMP1 gene determine the speed at which tuberculosis develops. Certain factors are already known to increase the speed at which people develop tuberculosis, however, prior to this study no link has been made between a gene and the speed at which the disease progresses.

“Understanding the basic pathways of pathogenesis offers new targets and policies for disease prevention,” notes Dr Emil Skamene, scientific director of the Research Institute of the McGill University Health Centre (MUHC).